Prestige LP颈椎椎间盘置换术后“张口不良”原因分析

Cause analysis for "reverse gape" after Prestige LP cervical disc replacement

目的探讨Prestige LP颈椎椎间盘置换术术后"张口不良"原因。方法 2008年2月～2010年3月行PrestigeLP颈椎椎间盘置换术26例。通过对患者术前及术后颈椎正侧位、动力位X线片及三维CT影像学资料的搜集和对比,分析Prestige LP颈椎椎间盘置换术术后"张口不良"原因,并对患者颈椎功能障碍指数(neck disability index,NDI)及颈部、上肢疼痛视觉模拟量表(visual analogue scale,VAS)评分,以及依据动力位X线片测量手术节段单间隙矢状面屈伸运动度进行统计学分析。结果 8例患者发生置换椎间盘"张口不良"。正常患者与"张口不良"患者术后VAS评分及NDI的差异无统计学意义(P>0.01),但"张口不良"患者术后颈椎活动度小于正常组,差异有统计学意义(P<0.01)。出现置换椎间盘"张口不良"患者中,1例术前存在颈椎结构性后凸,术后颈椎后凸无改善;5例置入椎间盘与上下相邻椎间隙不平行,提示椎间隙处理不准确;1例椎间隙处理中椎体后缘骨质切除过多导致置换椎间盘"张口不良"。结论 Prestige LP颈椎椎间盘置换手术操作较简单方便,但手术依赖术者主观性和经验性较多,手术本身客观性和精确性较少,易出现局限性后凸和椎间盘"张口不良"。术后椎间盘"张口不良"不影响患者症状改善,但影响术后颈椎活动度;要获得满意的间盘动-静态平衡,需要严格掌握适应证、遵循手术关键原则和一个较长的学习曲线。

Objective To analyze the reasons for ＂reverse gape＂ after Prestige LP artificial cervical disc replacement.Methods Twenty-six patients who received Prestige LP disc replacement from February 2008 to March 2010 were enrolled in this study.They were all followed up for at least 2 years.Their radiographs including X-ray films at anteroposterior and dynamic positions,and 3D CT were collected and compared.Neck disability index（NDI）,visual analogue scale（VAS） score of neck pain and brachialgia,and cervical range of motion at operated level were evaluated.Results Eight cases with 9 discs（31%） were found with ＂reverse gape＂ according to postoperative data.Though there was no statistically significant difference in VAS score and NDI between ＂reverse gape＂ group and normal group（P〉0.01）.Dynamic X-ray films showed statistically significant difference in cervical range of motion between 2 groups（P〈0.01）.Of the 8 patients,one with preoperative cervical kyphosis had no change postoperatively,5 cases were due to incorrect preparation of intervertebral space,and one due to too much osteophyma excision in the inferior plate.Conclusion Although the surgical techniques in Prestige LP artificial disc replacement are simple,the surgery depends too much on the surgeon＇s subjectivity and experience,but not on the surgery itself and subtle instruments,which results in cervical kyphosis and ＂reverse gape＂.The clinical symptoms are improved after operation,but ＂reverse gape＂ limits cervical range of motion.In order to obtain satisfactory outcomes,cervical spine surgeons need to follow the indications and operation guide strictly.